I think it would be a good idea to add an UI element that shows What interactions are available for which characters on which machine.
Kinda like the Graph in the game Breeders of the Nephelym. Basically a chart that shows the requirements for a specific action.
X would check for Penis (true/false boolean) for the player
Y would check for scale within a certain range (float value) for the player
A; B same as above but for the current selected NPC, either in the test tube or on a machine.
this would make it easier to see the "whole picture" when it comes to How much content is actually in the game.
It would also make it easier for people to do certain actions without guides or cheats.
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